ALS Symptoms and Treatment
ALS presents with progressive muscle weakness in two main patterns—bulbar onset (affecting speech and swallowing) or limb onset (affecting arms/legs)—with bulbar onset carrying worse prognosis (median survival 25-28 months versus 44 months for limb onset). 1, 2
Clinical Presentation and Symptoms
Initial Symptoms by Onset Type
Limb-onset ALS (two-thirds of cases):
- Focal muscle weakness and wasting starting distally or proximally in upper or lower limbs 3
- Progressive spasticity developing in weakened limbs, impairing manual dexterity and gait 3
- Muscle atrophy and hyperreflexia 4
Bulbar-onset ALS (one-third of cases):
- Dysarthria (speech difficulties) and dysphagia (swallowing problems) for solids or liquids 3
- Limb symptoms develop almost simultaneously or within 1-2 years 3
- Sialorrhea (excessive drooling) due to impaired swallowing 2, 5
- Nasal regurgitation 2
Progressive Symptoms Common to Both Types
- Pathological crying or laughter (pseudobulbar affect) 5
- Muscle cramps and spasms 5
- Spasticity 5
- Severely limited mobility in later stages 4
- Respiratory failure (primary cause of death) occurring 2-3 years after bulbar onset or 3-5 years after limb onset 3
Dysphagia Progression Stages
Dysphagia progresses through 5 distinct stages: normal eating habits → early eating problems → dietary consistency modifications → tube feeding requirement → nothing by mouth (NPO) status 1, 2
Diagnostic Approach
Essential Diagnostic Workup
- Electromyography (EMG) showing denervation and reinnervation patterns in multiple body regions 1
- MRI head without IV contrast to exclude other conditions (abnormal T2/FLAIR signal in corticospinal tracts is common) 1
- Clinical history and examination demonstrating upper and lower motor neuron signs not explained by other disease 3
Dysphagia-Specific Evaluation
All patients with suspected bulbar dysfunction require swallow screening before initiating oral intake. 2
- Videofluoroscopy (VFS) should be performed at diagnosis to detect early dysphagia, even in asymptomatic patients with bulbar symptoms 6, 1, 2
- VFS detects oral stasis, piecemeal swallowing, incomplete upper esophageal sphincter relaxation, and silent aspirations 6
- Fiberoptic endoscopic evaluation of swallowing (FEES) can identify impaired chewing, tongue muscle deficit, and pharyngeal residues 6
Treatment Options
Disease-Modifying Medication
Riluzole 50 mg twice daily (taken at least 1 hour before or 2 hours after meals) is the FDA-approved treatment that extends survival. 7, 3
- Monitor serum aminotransferases before and during treatment 7
- Discontinue if liver dysfunction develops or baseline aminotransferases exceed 5 times upper limit of normal 7
- Advise patients to report febrile illness due to neutropenia risk 7
- Discontinue if interstitial lung disease develops 7
Nutritional Management
Conduct nutritional status assessment (BMI, weight loss) every 3 months to detect early malnutrition. 1, 2
For patients with dysphagia:
- Adapt food texture to facilitate swallowing 1, 2
- Implement postural maneuvers 1, 2
- Use thicker liquids and semisolid foods with high water content instead of thin liquids 1, 2
- Eat frequent small meals to prevent weight loss 5
Enteral nutrition via gastrostomy:
- Place PEG before respiratory function significantly deteriorates, ideally when FVC remains >50% of predicted 2
- Refuse gastrostomy when FVC falls below 30% 2
- Preferably use percutaneous endoscopic gastrostomy (PEG) or radiological gastrostomy 1, 5
Respiratory Management
Establish baseline pulmonary function with slow vital capacity (SVC) and peak cough flow (PCF) measurements. 1
Initiate non-invasive ventilation (NIV) when:
- FVC <80% of normal with symptoms 2
- FVC <50% predicted 2
- Evidence of sleep-disordered breathing or hypoventilation on polysomnography 2
Use bilevel positive airway pressure (BPAP) with backup respiratory rate for better patient-ventilator synchrony in patients with bulbar impairment. 2
Symptomatic Treatment
Sialorrhea management:
- First-line: inexpensive oral anticholinergic medication 2
- Second-line: botulinum toxin A injection into salivary glands 2, 5
- Alternative: radiotherapy to salivary glands 5
Other symptomatic treatments:
- Cramps, spasms, and spasticity: medication (specific agents not detailed in guidelines) 5
- Pathological crying or laughter: medication 5
- Excess mucus in respiratory tract: anticholinergics 5
Communication support when speech becomes unintelligible:
- Sign language, mime, posture 5
- Communication apparatus ranging from note pad to advanced computer systems 5
Palliative Care Integration
Adopt a palliative care approach from the time of diagnosis, not reserved for end-stage disease. 1, 2
- Early referral to palliative services to establish relationships before communication becomes severely limited 1, 2
- Initiate end-of-life discussions at trigger points: patient distress, disease evolution, or patient's expressed desire 2
- During terminal phase, prioritize treatment of restlessness, anxiety, pain, and dyspnea 5
Critical Care Coordination
Multidisciplinary care improves both survival and quality of life, requiring coordination among neurology, pulmonology, gastroenterology, speech-language pathology, nutrition, physical therapy, occupational therapy, social work, and palliative care. 2
- All equipment and service requests for ALS should be considered urgent and handled expeditiously to avoid catastrophic safety risks 2
- Provide special mobility equipment much earlier than for other muscle diseases due to rapid ALS progression 5
- Assess for cognitive impairment and executive dysfunction, which increase risk of falls, choking episodes, and injuries, and adversely affect NIV compliance 2